Apparatus for producing molded pulp articles



Mack 18, 1941.

.W. H. RANDALL ETAL APPARATUS FOR PRODUCING MOLDED PULP ARTICLES Filed April 29,1937

6 Sheets-Sheet '1 In axe/Liamnzzermndau RzchardI.Erzze/ry March 18, 1941;

w. H. RANDALL ETAL 2234,9749

AYPARATUS FOR PRODUCING MOLDED PULP ARTICLES Filed April 29, 1937 sheets shaet 2 a 8 1 E I'M-1|- 31115 t rs: n lier if Randall Ric/lard L. Emery s at; '2

(Ittorneg March is, 194

w. H. RANDALL ETIAL 34.979

APPARATUS FOR PRODUCING MOLDED PULP ARTICLES Filed April 29, 1937 6Shaets-Sheet 5 :3: 3 v I 1 a7 36 A v F I 7: E x, Y 5 2 E ()43 mg- -1 i i nujl] 4g J .ZhUeIZZO/GY Mzzer Anemia 19m Ric/zardlE/rzeg 44 fliiorzzegl.

Mar'ih I w. H. RANDALL ErAL 234.979

APPARATUS FOR PRODUCING MOLDED PULP ARTICLES K Filed April 29. 1 957 e Sheets-Sheet 4 jam; 2 Vlier/[Randaf on? Rzlc/zard'L.Z/nery ch 18, 1941. w. H. RANDALL ETAL 2234379 APPARATUS FOR PRODUCING MOLDED PULP ARTICLES Filed April 29, 1937 6 Sheets-Sheet 5 In wen-lo n95 Mam}! 3, 9 w. H. RANDALL ELTAL ,979

APPARATUS FOR rnunucme MOLDED rum ARTICLES Filed April 29, 1937 s Sheets-Sheet s Iuvm'rons.

Walter HRandall .Richard Po ms Mar. 18, 1941 r Walter H. Randall and Richard 1.. Emery, Waterville, Maine, assignors, by mesne ents,

to The Canal National Bank of Portland, Portland, Maine, a national-banking association of the United States, as trustee Application April 29, 1937, Serial No. 139,734

18 Claims.

This invention relates to improvements in machines and methods for the production of both single and multi-layer molded pulp articles.

, Its general object is to provide a commercially satisfactory machine and method for forming,

drying, and finishing such articles.

In the simplest embodiment (Fig. 'i) oi our invention for producing a single layer molded pulp article, we mount a single forming die and a single drying die on an intermittently rotating shaft and mount outside of the orbit of these revolving dies a single reciprocating drying die which is adapted to coact with the dies on the rotating die unit. Below the intermittently rolii tatlng die unit is mounted a pulp tank which is adapted to be raised and lowered for the immerslop oi. the forming die at the proper time. for the suction formation of an article thereon.

The article formed on the forming die remains w thereon while the rotating die unit steps ahead and until the forming die is brought into registration with the reciprocating drying die. Thereupon, the reciprocating drying die closes on and retracts from the forming die to transfer the formed article to itself.

The article remains on the reciprocating dry ing die until the continued stepping oi the rotating die unit brings the revoluble drying die into a position for registration with the reciprogo eating drying die, whereupon the reciprocating drying die with its wet article closes on the revolpble drying die to completely dry and finish the article between these two dies and then retracts, otter which the dried article is ejected from the machine in any convenient manner.

During the period in which the artitcle is being dried the forming die is immersed in pulp stock for the suction formation of another article thereon.

In the simplest embodiment (Fig. 9) of our invention for producing a multi-layer molded pulp article, ,we mount a pair of forming dies and a drying die on the intermittently rotating shaft and mount outside the orbit of these revolving dies at single reciprocating drying die which is adapted to onset with the dies on the rotating die unit.

Below the intermittently rotating die unit is mounted a double compartment tank which is adapted to be raised and lowered for the simultaneous immersion of the forming dies in the respective compartments of said tank at the proper time for the suction formation of article layers thereon.

The articles formed on the forming dies remain thereon while the rotating die unit steps ahead and until the forming dies are successively brought into registration with the reciprocating drying die. Thereupon the reciprocating drying die closes on and retracts from each forming die 5 -to successively transfer the pulp layers to itself.

The composite article remains on the reciprocating drying die until the continued stepping of the rotating die unit brings the revoluble drying die into a position for registration with the re-' 10 ciprocating drying die, whereupon the reciprocating drying die with its composite wet article thereon closes on the revoluble drying die to completely dry and finish the article between these two dies and then retracts, aiter which the dried 18 article is ejected from the machine in any convenient manner.

During the period in which the composite article is being dried the forming dies are immersed in the compartments of the pulp tank for the 20 suction formation of other article layers thereon.

Thus the individual article layers are formed on independent forming dies, consolidated together under pressure, and the composite article dried, bonded and finished under heat, vacuum 25 and mechanical pressure in the form of the desired commercial article.

In our preferred embodiment (Fig. 8) for producing a single layer article, we mount a pair 01' oppositely disposed forming dies and a pair of oppositely disposed drying dies on an intermittently rotating shaft, and we mount outside the orbit of these revolving dies 9. pair of oppositely disposed reciprocating drying dies, one of which may be an ejecting die.

. Beneath the rotating unit we mount a pulp tank adapted to be raised for successively immersing the iorming dies for the suction iormation of individual articles thereon when thetank is raised, as required, towards the die unit. 40

The suction-formed articles remain on the forminmdles during stepping of the rotating die unit and until each forming die reaches a position for registration with the reciprocating drying die, whereupon said reciprocating drying die closes on and retracts from each forming die to transfer the article to itself.

Thereafter, in the continued stepping oi the rotating die unit, the article on said reciprocating drying die is contacted with a revoluble drying die to completely dry and finish the article between these two dies.

After drying the article is transferred, in the continued stepping of the machine, from said reciprocating drying die by means of said revolull pair of oppositely disposed reciprocating drying dies outside the orbit of these revolving dies.

Beneath the rotating die unit, we mount a double compartment pulp tank within the respective compartments of which two circumferentially adjacent forming dies are adaptedto be simultaneously immersed for the suction formation of individual article layers thereon when the tank is raised, as required, towards the die unit.

Such article layers remain on said forming dies during stepping of the rotating die unit and until each forming die reaches a position. for registration with one of the reciprocating drying dies, whereupon said reciprocating drying die closes on and retracts from each forming die to successively transfer the article as a composite article.

Thereafter, in the continued stepping of the rotating die unit, the composite article on said reciprocating drying die is contacted with one of the revoluble drying dies of: the rotating die unit and consolidated underupressure, and bonded, partly-dried and finished under heat, vacuum and mechanical pressure between these two dies. 1

After drying to a predetermined degree, the composite article is transferred, in the continued stepping of the machine, from said first reciprocating drying die, by means of said revoluble drying die, to the second reciprocating drying die where the drying and finishing of the composite article is completed between these two dies, after which the second reciprocating drying die removes the finished article from the revoluble drying die and ejects it from the machine.

In the accompanying drawings we have shown the simplest and the preferred embodiments of our invention, together with several variations thereof which are suggestive of the many possible modifications in design for achieving our object.

Fig. 1 is an end elevation, partly in section, through so much of our preferred machine for producing a multi-layer article, as is necessary for an understanding of the forming, consolidating, and drying operations.

Fig. 2 is a detail showing one method of intermittently rotating the stepping unit and locking the same in each paused position for proper registration and coaction of the dies, and also showing conventional means for controlling the various reciprocating elements of the machine in their properly timed relationship.

Fig. 3 is a view similar to Fig. 1 showing a showing still further modifications.

layers to itself Fig. '7 shows the simplest embodiment of our invention for producing a single layer article.

Fig. 8 shows a machine similar to Fig. 7 but producing two single layer articles at each complete revolution of the rotating die unit.

Fig. 9 shows the simplest embodiment of our invention for producing a multi-layer article.

Fig. 10 shows a machine similar to Fig. 8 but in which the revolving dies are female and the reciprocating dies are male, and

Fig. 11 shows a machine generally similar to Fig. 1, but in which the revolving dies are female and the reciprocating dies are male.

In Fig. 1, we have shown our preferred machine for makingjmulti-layer articles. Such machine comprises a single step-by-step rotating die unit i mounted on drive shaft [0 and provided with radial arms Ia on which is mounted a plurality of equi-distantly spaced dies 2A, 23, 3A, 3B, and 5A and 13.

The dies 2A'and 2B are forming dies for the suction formation of individual article layers from one grade of pulp stock, and are arranged diametrically opposite one another. The dies 3A and 3B are forming dies and are foraminous as indicated at F for the suction formation of in dividual article layers from another grade of pulp stock, and are likewise arranged diametrically opposite one another. The dies 4A and 4B are revoluble drying dies for drying and finishing the composite articles, and are also arranged diametrically opposite one another between the dies 2A and 3B and 3A and 23 respectively. The dies 4A and 13 are heated in any suitable manner, as indicated at H. v

A pulp tank having double compartments 1 and 8 containing different grades of pulp stock is adapted to be raised and lowered relative to the die unit l. When said tank is raised, the forming dies 2A and 2B and 3A and 3B are immersed in proper sequence in the proper pulp compartments of the tank.

Reciprocating drying dies 5A and 5B are mounted at opposite sides of the revolving unit I outside the orbit of the rotating dies on said unit, but in line with the paused positions thereof for coaction with said revolving dies as may be required.

The die 5B in addition to coacting with the required dies on rotating die unit I is an ejecting die for ejecting the dried and finished article from the machine.

The machine illustrated in Fig. 1 forms one complete two-layer article every half revolution of the intermittently rotating unit. The forming dies 2A and 23 each mold one layer of the composite-article, as for example, a lining layer.

.The forming dies 3A and 3B mold another layer of the composite article, as for example, a body or backing layer. The revoluble drying dies 4A and 4B coact with the reciprocating dies'5A and 53 to bond, dry and finish the composite articles underheat, vacuum and mechanical pressure,

and are foraminous as indicated at F and aretating the die unit I step by step. For purposes oiillustration we have shown in Fig. 2 a stepping wheel lb of modified Geneva. type fast on the drive shaft lc. The periphery of the stepping wheel is provided with a series of radial slots '6 Id corresponding in number and spacing to the number and spacing of the dies on intermittently rotating die unit I. V

successively coacting with the slots Id is a roller le carried by a driving arm If fast on a 1 drive shaft lg which is continuously rotated from I any smtable power source and acts to rotate the steppin wheel and with it the rotating die unit in the direction of the arrow the distance of one die space at each step in the cycle of the machine.

1 In order to lock the stepping wheel for proper registration and coaction of the rotating dies on unit I with the reciprocating dies IA and 53 as required, we provide an automatic latch lh adapt- 29 ed to be successively entererd into and withdrawn from a series of locking notches 'lk located in the periphery of the stepping wheel intermediate of the slots Id. The locking latch is operated in timed relation to the operation of the driving 55 arm I in any suitable manner, as by a suitably timed cam mechanism or as by the hydraulic or air operated cylinder lm 0! Fig.2.

Obviously, of course, other well known means,"

either mechanical or hydraulic, maybe provided so for accomplishing this two-fold function of steppingand locking the rotating die unit.

The reciprocating drying dies IA and 5B are toraminous as indicated at F and are provided with connections for the application of vacuum to the article for removing the steam vapors given oil. by the article during dryin and also to permit air pressure to be used for the transfer or the articles from the dies IA and IB'to coacting dies as may be required.

ill The dies IA and 513 may or may not be heated, as desired. They are reciprocated into coacting relation with the several dies of the intermittently rotating die unit at the proper time by any suitable mechanism, as for example, the bydraulic operating cylinders I shown in Fig. 1.

Obviously, however, such dies may be operated mechanically rather than hydraulically where desired.

The double stock tank I and 8 is shown as hydraulically operated by means 0! the hydraulic cylinder 8, but obviously may he raised and lowered mechanically rather than hydraulically if so desired. The operation of the various hydraulic cylinders H, I and in may be controlled by means of cam operated valve mechanisms as shown'in Fig. 2. Cylinder im and the cylinder I, which controls die IA, are controlled by valve I" which is actuated by a timing cam Ill, fast on drive shaft la, and rocker lever I02. Hy-

draulic connections ill areprovidedbetweenvalve III and said cylinders. This timing valve ill will actuate the latch in and die IA once for each step of the rotating unit. Cylinder 9 and cylinder I, which controls the die IB, are controlled by valve [14 which is actuated by a timing cam III, fast on shaft III, and rocker lever illl. Hydraulic connections ill are provided between valve I04 and said'cylinders. Shait Ill is driven irom shaft la by gears II! and ill. 7 The ratio between said gears is such as to actuate pulp tank 1-! and die IB once every third step of the rotating unit. Fluid under pressure is supplied to valves Ill and Ill from any suitable source. Alternatively, ii! desirable, an individual 18 control valve and operating mechanism may be i-ions of an article cycle are designated Nos [-8 inclusive. I

Ibrpurposesofillustrmtionpositional l may' beconsidered asastartingpositlon. Inthispositiontherotatingdieimit i haspausedinits rotation andhasbeenlockedinitspausedw sition. The double stock tank has been raised 1. to immerse the forming dies 2A and IA in the pulp mixtures contained in the respective compartmentslandlo! said tank.

The individual pulp layers c and d deposited on the other set of forming dies 23 and 313 at 1 a previous stage or the die cycle are now draining on said dies, vacuum being maintained on said dies 23 and 313, during their dwell time in this position to facilitate the fur-flier removal of moisture from the layers c and d thereon, The reciprocating drying dies IA and II! are closed on the complemental revoluhle drying dies 7 4A and 43, respectively,- and these several dies are combinedly drying between them the composite articles e and j which were formed at we vious stages in the cycle or the machine.

The partsremain in the #i posiiton for an interval ot time which is determined by the required drying period for the composite articles e and I being dried between the dies 4A and IA and 4B and 53 respectively. During this drying time, article layers It and a are being formed on l'lorming dies 2A and 3A immersed in pulp tan]:

At the end of the drying period the dies IA and 53 are retracted from dies 4A and 4B respectlvely' and the tank 1-! is lowered away i'rom the forming dies 2A and 3A (see position #2). The composite article e shown drying between the dies 4A and IA in position #I is at (a this time partly dried and remains on the rev-- oluble drying die 4A when the die IA is retracted. The composite article 1 shown drying between revoluble drying die 43 and die SE in position #i is completely dried at this aage or the ma- 4:

' chine cycle and is transferred to the die IB which after retraction swings so that the article may be ejected therefrom (see position #1) by means of a blast of compressed air through said die.

The die unit now steps one sixth of a revolu- 50 tion ahead to the #3 position. The forming die 33 with its previously deposited layer of pulp d thereon is now opposite die IA which has'closed thereon and then retracts from die 33 as shown in the #4 position of the diagram, removing the 68 article layer d from the forming die 3B and retaming it on itself.

As soon as die IA has retracted from die 3B, the die unit I steps ahead another step to the #I position or the diagram. This brings forming die In ID with its previously deposited layer 0 thereon opposite die IA on which is retained the article layer 42 previously removed from forming die 33 at position #4 of this diagram.

The die IA now closes on the forming die 2B 6! (see position #I) and then retracts (see position #1) from said die, thereby removing the previ-' ously deposited layer 0 from said forming die so that said die IA now has on it a two-layer article consisting of the first layer d which was removed I0 from forming dielB at position #4 and the second layer 0 which was just removed from forming die 23 at position #1. I

The machine now steps ahead to the #4 position of the diagram where the die II, which hll II ejected its article I, is shown as having swung back through its 90 arc and aligned itself with the die A of the rotating die unit. In this position die 5B is in readiness to coact with die IA for completing the drying and transferof the partly dried composite article e on die 4A, and the companion die 4B is positioned opposite the die 5A in readiness to coact with the composite article cd on die 5A.

Forming dies 2B and 3B now occupy the positions formerly occupied by forming dies 2A and 3A (see position #I) and are thus in readiness to be immersed in the double compartments of the pulp tank when said tank is again raised.

With the closing of dies 5A and 5B on the revoluble drying dies 43 and 4A, respectively, the die 5A and die 4B will start to dry the composite article cd, and die 5B and die 4A will finish drying the composite article e previously partly dried between die 4A and die 5A at position #i.

At or substantially at this time the stock tank is raised and forming dies 23 and 3B are immersed therein ready for the formation of new article layers, the pulp layers h and g theretofore deposited on the other set of forming dies 2A and 3A bein in draining position during the cycle of drying the articles between dies 4A and 5B and 4B and 5A. The cycle of die movement at this moment is stationary for a length of time as may be required for the drying and finishing of the composite articles, at the completion of which drying period the machine repeats its cycle.

It is evident from the foregoing description that die 5A coacts with each and every die on the rotating unit whereas die 53 coacts only with dies 4A and 4B. The me SE, however, performs the dual function of completing the drying and finishing of the partly dried articles on dies 3A and 4B and also of removing them from the rotating unit and ejecting them from the machine. It is also evident that a full rotation of die unit 8 forms, dries and ejects two finished articles and that a cycle completing the manufacture of one article is equivalent to a half revolution of the rotating die unit.

Thus, we form a two-layer article, the layers of which, are formed on independent forming dies mounted on a common shaft and then transfer these layers in proper sequence to a reciprocating drying die on which they are first consolidated under pressure and afterwards bonded, dried and finished under heat and mechanical pressure between the revolubledrying dies carried on the rotating die unit andthe reciprocating drying dies mounted outside the orbit of the revolving The drying of the article under pressure dies. between two complemental drying dies of the required shape prevents any appreciable shrinkage and results in a finished article which is true to the required shape and size.

While the machine herein shown and described has only one unit of dies, it is evident that two or more units of dies may be mounted adjacent to each other on a common drive shaft with their required coacting reciprocating drying dies suitably mounted onth'e machine frame and with a properly proportioned tank. in which to immerse the multiple sets of forming dies.

It is also obvious that by mounting the formin dies for the formation of each grade of material making up the composite article and the revolve ble drying dies vfor the drying of the article on a common rotating unit we greatlysimpliiy the mechanics of the machine and reduce to the minimumthenumberotpartsandsizcotma chine required for the manufacture of this type of article.

If desired, we may provide one or more reciprocating pressing dies 5 opposite the forming dies 23 and 3B in Fig. 1. The dies 5 may be used for pressing additional moisture from the respective article layers on the several forming dies during the time the forming dies are paused opposite the dies 5 such moisture being expelled through the forming dies themselves. Optionally, the dies 5 may be heated for the purpose of preheating the article layers to accelerate drying after the two layers have been consolidated on die 5A.

Obviously, also, if desired, the die 53 may be omitted and the drying of the compositev article completed on die 5A, which die can be adapted to retract with the article and swing to a position where the dried article may be ejected from it as described for die 53.

In the modification, Fig. 3, we show a form of our machine in which the intermittently rotating shaft it carries four equally spaced dies l2, id, id, and it. This die unit may be intermittently driven in the same manner as the fcrm shown in Fig. 1, except that it is a four step unit instead of a six step unit as in Fig. 1, and may be locked at each pause in its rotation in the same manner as described for Fig. 1.

Mounted on the machine frame and arranged to reciprocate relative to the orbit of the revolving dies is a reciprocating die I5. This is reciprocated in any desired manner as by means of the operating cylinder l9 and successively c0- acts with each of the revolving dies whenthese dies are passed or at dwell in their rotation opposite the reciprocating die l5.-

A double stock tank having compartments ii and ill for difierent grades of pulp is arranged beneath the rotating die unit and is raised and lowered in any suitable manner as by the operating cylinder 20. The timed operation of cylinders it and 2 may be controlled by means of a cam-operated valve mechanism similar to that shown in Fig. 2. v

The die i2 is a forming die for the formation of a pulp layer from one grade of stock while immersed in tank compartment ill. The die i3 is a forming die for the formation of another layer of pulp from a second grade of stock while immersed in tank compartment it. Both dies are foraminous as indicated at F.

The die it is a reciprocating drying die to which are successively transferred the pulp layers from the forming dies it and. i2. The die I6 is foraminous as indicated at F for applying vacuum to remove the steam vapors during the period in which thearticle is being dried be tween it and the revoluble drying die M and for applying air pressure to transfer the article to the ejector die it. If desired, heat may be applied to the die It in any suitable manner. The die it is heated as indicatedat H.

The ejector die It is foraminous as indicated at F and functions to remove the article from die Shatter it is dried and carries it to dotted line ejecting position marked iii where the article is ejected from said ejector die as by means of a blast of air.

In diagram of Fig. 8 the successive positions of an articlecycle are designated from Ml inclusive.

For purposes of illustration position #I may be considered as a starting position. In position #I, the rotating die unit II has paused in its rotation and the double stock tank iI-li has been raised to immerse the forming dies l2 and II in the respective compartments thereof; The revoluble drying die l4 and the reciprocating drying die I! are drying a previously formed composite article a" therebetween.

After an interval of time required for the complete drying of the composite article 1' between the dies II and i5, and during which period indivldual pulp layers l and]: have been deposited on forming dies l3 and it, the die II retracts from the die l4 (see position #2) carrying with it the completely dried composite article 1.

The-stock tank is now lowered so that the forming dies l2 and I! are no longer immersed therein and the rotating unit I l steps one quarter applied to ejector die It and air pressure applied to die is. r

As soon as die it has retracted after transferring the composite dried article i to ejector die I, the rotatingdie unit Ii steps ahead one quarter revolution '(see position #4) bringing form-' ing die I3 opposite die II which now closes on and retracts from forming die l3, removing the layer of pulp l therefrom.

As soon as die l5 has retracted carrying with it the'pulp layer 1 from forming die ii, the machine steps one quarter of a revolution as shown in position #5, bringing forming die I: opposite die IS.

The die i5, which is already carrying the pulp layer 1 previously removed from forming die ll at position #l, now closes on and retracts from forming die i2, removing the pulp layer I: therefrom as shown in position #5.

The die I! now has a two layer article on it consistin of the layer I removed from forming die I! at position #4 and the layer It removed from forming die I! at position #5. a

As soon as the pulp layer It is removed from the forming .die I! at position #5, the rotating unit ii steps one more quarter turn to position #6, bringing revoluble drying die I again opposite die it. Thedie [5 with its two-layer article thereon nowcloses on die II as shown in position #8 and remains in this position under mechanical pressure until the composite article is dried,

line ejecting position marked 2! in position #6.

Stock tank il -48 remains in the down position until forming dies l2 and I3 have deposited their articles on die I! and made a complete revolution and returned to position #6 of the diagram.-

As soon as the forming dies i2 and llhave V returned to position #i, tank "-48 is again raised (see position #I), to again immerse the forming dies in the pulp stock and suction is again applied to both dies to cause new pulp layers to be deposited onthem. The composite article lc-l isbeing dried between dies :4 and ii, during this formation period.

- with this machine as with the form shown in Fig. 1 the raising and lowering of the tank ill-ll and the reciprocation of die It may be accomplished by mechanical means such as cams, etc. if desired, instead of by the hydraulic cylinders 20 and II, as shown.

Air and vacuum for the formation and transfer of articles are supplied to the rotating die unit through port boxes and timed by a valve cam shaft as is customary. Vacuum and air with proper timing are also provided on die i5.

A still further modified form of our machine is shown in Fig. 4, this being substantially the same as that of Fig. 3 except for the arrange-' ment for providing pulp stock to one of the two forming dies.

In the modification, Fig. 4, the intermittently rotating die unit 3! carries four equally spaced dies 32, 33, 34 and 36. This unit is rotated in progressive steps, one quarter of a revolution each step by mechanism similar to that described. in Fig. 1.

A reciprocating drying die 35 is mounted outside of the orbit of the revolving dies and is re- 'ciprocated by means of operating cylinder 3! or its equivalent into timed coaction with each of the dies on the rotating die unit 3!.

The stock tank 38 is raised and lowered by means of cylinder It or its equivalent. This tank is a single tank and provides stock only for the formation of a pulp layer on forming die 33. The timed operation of cylinders 39 and II may be controlled by means of a cam-operated valve mechanism similar to that shown in Fig. 2.

Stock for the formation of a pulp layer on forming die 32 is provided by means of an open faced bucket or stock container 31, the open face of which is held sealed to the ring of the forming die 32 duringthe formation period as in Fi 4.

' any further stock from tank I to container 31,

and allowing the surplus stock in container 31 and its connecting pipes to drain into drain tank 42.

As soon as this drainage is completed, container 31 is moved to the dotted line position shown in Fig. 4 so as to give clearance for revolving the die 32. If desired, a pump 43 is pro vided to pump surplus stock from tank 42 to tank .4!

The functions of the various dies are as follows:

The die 32 is a foraminous forming die for the formation of one grade of stock which is carried in tank 4! and formed by the bucket method as above described.

The die '33 is a foraminous forming die for forming a second grade of stock while immersed in. tank 38.

The die 34 is a revoluble drying die, and is heated as indicated at H.

The die 35 is a repricating drying die to which is successively transferred the pulp layers from the forming dies 33 and 32. Die 15 is foraminous as indicated at r' and is provided with drainage for'applying. suction to .the article and for removing the steam-vapors during the period in hit - forming die 81 carrying a previously formed artito and then retracts, removing from the die I! the dried article p which had previously been dried betweendie i9: and die H. Pressing die II coacts with forming die 88 for the purpose o1 squeezing additional moisture from article '1 It then retracts.

through the forming die GI. leaving article q on forming die 68.

As soon as the article 1 being dried between die i and vacuum die I l is dried to the required degree, die 1| retracts leaving article 1' on die II and the rotating die unit ll rotates one quarter of a revolution. This brings forming die til with article q thereon adjacent to die II. The die H then coacts with forming die 68 and re tracts removing article q from forming die Bl. During this interval ejector die 12 will swing to dotted position and eject the dried article 1) from the machine by means of a blast of air or otherwise.

Assoon as the die II has retracted removing article 1; from forming die 68, rotating die unit ii again steps one quarter revolution bringing die adjacent to die H. The die II with wet article q removed irom forming die 8 then coaots with die 85 and these dies stay in coaction ior an interval of time required to dry the artiale to a required degree. During this drying interval pulp stock tank H is again raised iminersing forming die 68 for the suction formation of an article thereon. Ejector die "I2 returns to a position for, coaction with die II and removes dried article T from this die for election from the machine. Pressing die 13 coacts with ole tor the purpose of squeezing additional molstare from this article through the forming die.

This completes one article cycle 01 the machine wl'iich is a 180 revolution of the rotating unit M, the machine having suction-formed, dried,

' a ed and ejected one single layer article.

In Fig. 9 we show a still further modification which is the simplest embodiment of our invention for producing multi-layer articles. This is based generally on the form of Fig. 3, but omits "the elector die ii of said iigure.

In this form of our invention the intermitteutly rotating die unit is indicated at ll.-The

aimin dies 82 and a: and the heated, drying die 84 are appropriatelymounted on the die unit ti. The double compartment pulp stock tank tt-tt is mounted below said unit for raising and lowering movements relative to the Iorming dies as required,'and the reciprocating Ioraminous drying die 81 is mounted outside of the orbit of the rotating dies for coaction therewith. The die I! may be heated by any suitable means it so desired.

The machine of Fig. 9 makes one two-layer article tor each complete revolution of the die unit. The cycle is generally similar to the machine of Fig. 3, except that the revoluble drying die M ejects the dried and finished article at an intermediate stage in the stepping or the die unit.

When the pulp tank is raised the foraminous i'oriningdies 82 and 83 are simultaneously immersed in the respective compartments of the tank for the suction formation of pulp layers thereon. When the tank is lowered and the ro-.

and retaining them upon itself as a composite article.

Alter die I! has removed the individual layers from the forming dies 83 and l2,-the continued stepping of the die unit brings the revoluble drying die 84 into line with the die 81, which thereupon closes on the die ll, to compress, dry, bond, and finish the composite article between these two dies. When the die 81 retracts, the dried and finished article is left on the die 84 and in the continued stepping of the machine is ejected therefrom as shown in dotted lines. When the article is thus ejected irom the machine die II is foraminous. 1

The modifications of Figs. and 11 are based on the machines of Figs. 8 and 1 but the die arrangement is reversed. In Figs. 10 and 11, all revoluble dies are female and all reciprocating dies are male, whereas in Figs. 8 and 1 all revoluble dies are male and all reciprocating dies are female.

The machines of Figs. 10 and 11 each form one article at each hall revolution or the rotating die unit or two articles for each complete revolution of such unit. The article formed by the machine of Fig. 10 is a single layer article, whereas that formed by the machine of Fig. 11 is a two-layer article.

swinging ejector die 59 are all mounted outside of the orbit of these revolving dies. Dies 91, 93, Si, 85, t1 and 99 are preferably ioraminous, and dies ll and 85 and El and 98 are preferably heated.- Die 98 does not need: to be foramlno unless used as an cjector die.

The article cycle is as Iollowsj:

Referring to Fig. 10 the rotating die unit M has just completed a 90 step and is in a station cry or paused position. The die M carries a pre viously dried article t which during this paused position is removed from this die by ejector die 99. Forming die 93 carries a previously formed article a which in this machine position is pressed and removed from forming die 93 by pressing and transfer die at.

The revoluble drying die 35 carries a wet article c which has previously been transferred to ltby pressing and transfer die 81. The reciproeating drying die 58 coacts with die 95 ima soilioient length oi time to dry the article 12 between gree, die Bl retracts leaving article 1; on die 95 and the machine makes one step ahead.

This will bring forming die 92 with its newly formed article thereon in a drainage position for the removal of additional moisture by means of air drawn through the article by application of vacuum to -the forming die. The revoluble drying die i l will be in a position for registration with pressing and transfer die II which will close on and retract from .die SI transferring the wet ar- 7 ticle' uto die 84. During'this period ejector die B will pivot to the dotted line position shown and the dried article-t will be ejected from the ejector die by means of. a blast offair. The die 98 remains retracted and pulp tank 96 remains lowered. v

Rotating die unit 9i now makes one step ahead. The revoluble drying die 34 with its wet article u previously transferred to it by pressing and transiier die 91 will have moved to a position in line with die 98. The die 88 will coact with die St for the drying of article it between these two dies. Ejector die 99 will remove dried article 1) from die and pressing die 91 will coact with forming die 92 and pulp tank 96 will be raised immersing forming die 93 for the suction formation of an article thereon.

This completes one article cycle of the machine which is a 180 revolution of the rotating unit and which has suction-formed, dried, finished and elected one article from the machine.

With this machine or that of Fig. 8 it is possible, if desired, to omit the ejecting die if or 99 and to remove the article from the machine at the die ll of Fig. 8, or the die 98 of Fig. 10, in which event the dies H or 98 would be mounted for both pivotal and reciprocating movements.

In the machine of Fig. 11, the intermittently rotating shaft is designated at l and the pulp stock tank disposed therebeneath is provided with double compartments 9 and a. Two oppositely disposed pairs of foraminous forming dies lZA, 52B, and NBA, iSB, respectively, are mounted on said shaft, as are two oppositely disposed pairs of revoluble drying dies MA and B. The dies iEiA and i513 may be heated if desired, and are foraminous and provided with connections for applying vacuum to hold the article layers thereon and to remove the steam vapors given oh by the drying articles.

Reciprocably mounted outside of the orbit of these revolving dies is a pair of circumferentially adjacent dies to and la and a pair of heated drying dies MA and MB, the die l lB also being foraminous and pivoted so as to function as an ejecting die. A

The die to is a wet transfer die for successively removing the article layers from the forming dies and then transferring the composite article to one of the dies 55A or HEB. Die 6a is foraminous and provided with the necessary air and vacuum connections for the transfer of the articles and article layers.

The die in is a pressing die for the purpose of squeezing additional moisture from the wet article layers through the forming dies. Die la may be heated if desired for preheating the article layers to accelerate drying ofthe composite article.

The article cycle is as follows:

With the pulp stock tank raised, the forming dies HA and i3A are immersed in the respective tank compartments for the suction formation of article layers thereon. Transfer die to coacts with a previously formed wet article layer on forming die 3. Pressing die-5a coacts with a p eviously formed article layer on forming die MB. The reciprocating drying dies MA and MB have coacted with composite articles on revoluble drying dies HA and i513, respectively.

The machine remains in this position until the composite articles between die iBA and die MA and die I53 and die B respectively are dried to the required degree, whereupon the pulp stoc k tank is lowered away from forming dies MA and NA leaving a suction-formed pulp layer of the required thickness on each forming die.

Wet transfer die 6a retracts from forming die IZB removing the article layer from this die.

Pressing die 1a retracts from the article layer on forming die MB. The die A retracts from the now partly dried composite article on die IIA. The die MB retracts from die I53 removing a completely dried article therefrom.

The rotating die unit now steps ahead one-sixth of a revolution and pauses. Transfer die in carrying the wet article layer which it had previously removed from forming die l2B coacts with the article layer on forming die i315 thus combining the two layers into a composite article. The

die MB swings 90 and is ready to eject the dried composite article which it is carrying.

Thereafter transfer die 6a retracts carrying with it the composite article made up of article layers successively removed from forming dies I23 and i328 and die MB ejects the composite dried article from the machine.

The rotating die unit now makes another step and pauses. While so paused the only action which takes place with reference to the reciprocating dies is the transfer of the wet multilayer article from transfer die to to die I513.

The die rotating unit lnow makes another step and pauses. While so paused the die i513 with its wet composite article transferred to it from transfer die 6a is in a position for coacting with die MA. The die 85A with its partly dried multi-layer article is in a position to coact with die MB for the completion of the drying of the article thereon. Forming die l2A with its article layer thereon has revolved to a position opposite to transfer die to. Forming die itB with its article layer thereon has revolved to a position opposite to pressing die la and all reciprocating dies now close on the articles carried by the dies adiacent to them. This completes an article cycle of the machine, it being noted that die ta. is the only die of the series of four reciprocating dies to, la, MA and MB which coacts with all of the dies of the rotating die unit. When so desired transfer die ta may be omitted and the pulp layers may be successively removed from the forming dies by die l iA in which event die MA is made foraminous. The die MA with its composite article is thereafter coacted with die 958 for a period of time required to dry the article as desired. Where die MA isalso used as a transfer die for removing the article layers from the forming dies, said die is provided with connections for applying vacuum for holding. the successive pulp layers thereon. Also, when so desired, die MB may be omitted and the composite article completely dried, bonded, and finished at die MA in which event die MA is also pivoted to function as an ejecting die.

In all forms, where the heated dies are used for transferring articles from one station to another, they are provided with drainage connections in their surface forthe purpose of holding the article on these dies by means of suction and for the transfer of these articles by means of air pressure.

In all forms, it is evident that the formed article is held under mechanical pressure between a pair of complemental drying dies, one of which is revoluble and the other of which is reciprocable, and that the article is dried bythe application of heat thereto from one or both of said d es.

Accordingly the term drying die as used herein is used to designate both the revoluble die (or dies) mounted on the intermittently rotating unit and the reciprocable die (or dies) mounted outside the orbit of the dies on said unit for timed coaction therewith.

'finish the wet formed article.

It is likewise a matter of choice whether the revoluble drying die or the reciprocating drying die, or both of them, be foraminous for the purpose of exhausting the water and water vapors given off by the drying article or for transferring the article from one die to another.

Various other modifications in machine and method may obviously be resorted to within the spirit and scope of our invention as defined by the appended claims. j

What we therefore claim and desire to secure by Letters Patent is:

l. A fibrous pulp molding machine, comprising an intermittently revolving shaft carrying two pairs of oppositely disposed foraminous forming dies and one pair of oppositely disposed drying dies, a first and a second oppositely disposed reciprocating drying die mounted outside the'orbit of the revolving dies for timed coaction therewith, means for depositing a layer of wet pulp on each of a pair of forming dies, means for revolving said shaft step by step to bring the dies thereon successively into coactive alinement with the reciprocating dies, means operative when said shaft is paused in its rotation for successively coacting said first reciprocating die with each of till hil

a pair of forming dies to remove the wet pulp layers from said forming dies in superimposed order and thereafter forcoacting said firstre ciprocating die carrying the superimposed article layers thereon with one of said revoluble drying dies to partly dry, bond and finish the composite article therebetween under mechanical pressure and heat applied-by at least one of said dies, means for retaining the partly-dried composite article on said revoluble drying die during that portion of the revolving travel of said revoluble drying die from said first reciprocating die to said second reciprocating die, and means operative when said shaft is paused in its rotation for coacting said second reciprocating die with the partly-dried composite article on said revoluble dialing die, to complete the drying, bonding and finishing of said composite article tlierebetween under mechanical pressure and heat applied by at least one of said dies and to remove the finished article and eject it from the machine.

2. The combination of claim 1, and a pressing and preheating die reciprocally mounted outside a 3. The combination of claim 1, the means for revolving the die shaft step-by step comprising a stepping wheel having a plurality of spaced slots corresponding in number and spacing to the number and spacing of the revolving dies, a drive shaft, an arm mounted on said shaft and carrying a roll adapted for successive entrance and withdrawal from said slots to step the wheel one step for each revolution of the drive shaft, and means for locking the revolving die shaft in paused position comprising notches in the stepping wheel and a latch for engagement with said notches adapted to be withdrawn when the step ping wheel is in motion and to be engaged when said wheel is at rest. Y

4. A flbrlll pulp molding machine comprising i an intermittently revolving shaft on which are mounted a foramlnous forming die and a drying die, means for depositing a wet pulp article on said forming die, a reciprocating drying die and a reciprocating and pivoting ejecting die mounted outside the orbit of said revolving dies at points spaced from each other, means for revolving said shaft step by step to bring the dies thereon successively into coactive alinement with the reciprocating drying die and with the ejecting die, means operative when said shaft is paused in its rotation for coacting the reciproeating drying dies first with the forming die to remove the wet article from the forming die and thereafter for coacting said reciprocating drying die carrying the wet article thereon with the revoluble drying die to dry the article between-said reciprocating drying die and said revoluble drying die under mechanical pressure and heat applied by at least one of said dies and leave the dried article on the revoluble drying die, means for retaining the dried article on the revoluble drying die during that portion of the revolving travel of said revoluble drying die from the reciprocating drying die to the ejecting dle, and means operative when said shaft is paused in its rotation for coacting the ejecting die with said revoluble drying die to remove the dried article from said revoluble drying die and eject it from the machine. 1

-5. A fibrous pulp molding machine, comprising an intermittently revolving shaft on which are mounted a plurality of forarninous forming dies and a plurality of drying dies, means for depositing a wet pulp article on each forming die, a plurality of reciprocating dies mounted outside the orbit of said revolving dies at points spaced from each other, at least one of said reciprocating dies being a drying die,fmeans for revolving said shaft step by step to bring the dies thereon successively into coactive alinement with the reciprocating dies, means operative when said shaft is paused in its rotation for coacting a reciprocating die with the forming dies to remove the wet articles from the forming dies and transfer them to the revoluble drying dies, means operative when said shaft is paused in its rotation for drying the articles between a reciprocating drying die and the revoluble drying dies under mechanical pressure and heat applied by at least one of said dies, means for retaining the dried articles on said revoluble drying dies during a portion of the revolving travel of said dies, and means operative when said shaft is paused in its rotation for coasting a reciprocating die with the dried articles on said revoluble drying dies to remove the dried articles therefrom and elect them from the machine.

6. A fibrous pulp molding machine, comprising an intermittently revolving shaft carrying two pairs of oppositely disposed i'oraminous forming dies and one pair of oppositely disposed drying dies, means for depositing a layer of wet pulp on each of a pair of forming dies, a reciprocating transfer die and a pair of oppositely disposed reciprocating drying dies mounted outside the orbit of the revolving dies, means for revolving said shaft step by step to bring the dies thereon successively into coactlve alinement with the reciprocating transfer die and with the pair of reciprocating drying dies; 'meansoperative when said shaft is paused in its rotation for successively coacting said transfer die with each of a pair of forming dies to remove. the wet article layers from said forming dies superimposing one layer upon the otherand to thereafter transfer the superimposed layers to a revoluble drying die, means operative when said shaft is paused in its rotation for coacting a reciprocating drying die with said revoluble drying die carrying the superimposed layers thereon for partially drying, bonding and finishing the composite article therebetween under mechanical pressure and heat applied by at-least one of said dies, means for retaining the partially dried composite article on said revoluble drying die during a portion of its revolving travel, and means operative when said shaft is paused in its rotation for coacting the other reciprocating drying die with .the partially dried composite article on said revoluble drying die to complete the drying, bonding and finishing of said article therebetween under mechanical pressure and heat applied by at least one of said dies and to remove the finished article and eject it from the machine.

'7. The combination of claim 6, and a pressing die reciprocably mounted outside the orbit of the revolving dies in advance of said transfer die for successive coaction with the article layers on the forming dies when said shaft is paused in its rotation.

8. A fibrous pulp molding machine, comprising an intermittently revolving shaft carrying two pairs of oppositely disposed foraminous forming dies and one pair of oppositely disposed drying dies, a reciprocating drying die mounted outside the orbit of the revolving dies, means for depositing a layer of wet pulp on each of a pair of forming dies, means for revolving said shaft step by step to bring the dies thereon successively into coaotive alinement with the reciprocating die, means operative when said shaft is paused in it's rotation for successively coacting said reciproeating die with each of a pair of forming dies to remove the wet pulp layers from said forming dies in superimposed order and thereafter to coact said reciprocating die carrying the superimposed article layers thereon with one of said revoluble drying dies to dry, bond and finish'the composite article therebetween under mechanical pressure and heat applied by at least one of said dies, and means to eject the finished article from the machine.

9. A fibrous pulp molding machine, comprising an intermittently revolving shaft carrying two pairs of oppositely disposed foraminous forming dies and one pair of oppositely disposed drying dies, means for depositing a wet pulp layer on each of a pair of forming dies,,a reciprocating transfer die and a reciprocating drying die' mounted at spaced points outside the orbit of the revolving dies, means for revolving said shaft step by step to bring the dies thereon successively into coaotive alinement. with .the reciprocating transfer die, means operative when said shaft is paused in its rotation for successively coacting said transfer die with each of a pair of forming dies to remove the wet article layers from said forming dies in successive order and to thereafter transfer the superimposed layers to a revoluble drying die, means operative when said shaft is paused in its rotation for coacting said reciprocating drying die with said revoluble drying die carrying the superimposed layers thereon to dry, bond and finish the composite article therebetween under mechanical pressure and heat applied by at least one of said dies, and means to eject the finished-article from the machine.

' 10. A fibrous pulp molding machine, comprising an intermittently revolving shaft on which are mounted a foraminous forming die and a drying die, means for depositing a wet pulp article on said forming die, a reciprocating drying die mounted outside the orbit of the revolving dies for timed coaction therewith, means for revolving said shaft step by step to bring the dies thereon successively into coaotive alinement with said reciprocating die, and means operative when said shaft is paused in its rotation for coacting said reciprocating die first with said forming die to remove the wet formed article from the forming die and thereafter with said revoluble drying die to dry the wet article between said revoluble drying die and said reciprocating die under mechanical pressure and heat applied by at least one of said dies.

11. A fibrous pulp molding machine, comprising an intermittently revolving shaft on which are mounted a pair of foraminous forming dies, a drying die and an ejecting die, means for depositing wet pulp layers on said forming dies, a reciprocating drying die mounted outside the orbit of said revolving dies, means for revolving said shaft step by step to bring the dies thereon successively into coaotive alinement with said reciprocating die, means operative when said shaft is paused in its rotation for successively coacting said reciprocating die first with said forming dies to remove the wet pulp layers therefrom and leave them superimposed on said reciprocating die, secondly with said revoluble drying die to dry, bond and finish the composite article between said dies under mechanical pressure and heat applied by at least one of said dies, and thirdly with said ejecting die for transferring the dried article to said ejecting die, and means for ejecting the finished article from said ejecting die;

12. The combination of claim 11, the means for depositing pulp layers on the forming dies comprising respectively a pulp tank adapted to be raised and lowered relative to the dies on said shaft for the immersion of one forming die and the suction formation of a pulp layer thereon when the tank is raised, and an open face pulp container mounted outside the orbit of the revolving dies and adapted to be moved into sealed contact with the other forming die, and means for filling said container with pulp stock for the suction formation of a pulp layer on said second forming die and for draining the container of surplus stock after the layer is formed and before the container is moved away from said second forming die to a position to clear the orbit of said die.

13. A fibrous pulp molding machine, comprising an intermittently revolving shaft, means for revolving said shaft step by step, two pairs of foraminous forming dies and one pair of drying dies mounted on said shaft, a double compartment pulp stock tank containing aqueous fibrous pulp mixtures disposed outside the orbit of said revolving dies, means for moving said tank towards said revolving dies for immersing two circumferentially adjacent forming dies therein for the suction formation of independent article layers on said forming dies and for thereafter lowering said tank to enable said revoluble drying dies to rotate through their orbit without immersion in the pulp mixtures, a pair of reciprocating drying dies mounted outside the orbit of the revolving dies, means for successively coacting one lit till

til

finish der and thereafter to partly dry, bond and said layers as a. composite article between said reciprocating die and one of said revoluble drying dies under mechanical pressure and heat ap rolled by at least one of said dies and leave the partly dried composite article on said revoiuble drying die, and means for successively coacting the other reciprocating die with the revoluble rlrylhtt dies only as each revoluble drying die with its partly dried composite article thereon is paused in its rotation opposite said last named reciprocating die to complete the drying, bondlnr and ilnishing oi the composite article on said revoluhle drying the under mechanical pressure and heat applied by at least one of said dies and remove the finished article therefrom.

til. it iilorous pulp molding machine compris hair a pulp tank containing an aqueous fibrous pulp titre, an intermittently revolving shaft on which are mounted a ioraminous forming die and a dryina die, means lor revolving said shalt step by step. means tor periodically raising and lotverinr the pulp taut: to immerse said tonming die in the pulp in :"vture tor the suction formation a. vvet article layer thereon and to enable the revoluhle drying die to rotate through its orbit vvlthoiit stolen in the pulp mixture, or reciprocating drying die mounted outside the orbit of the revolving dies ior timed coaction therewith, means operative when said shaft is paused in its rotation tor first coasting said reciprocating drydie with said forming die to remove the wet article lrom the forming die and 'for thereafter enacting said reciprocating drying die with the revoluble drying die to dry the wet article therehetvveen under mechanical pressure and heat applied by at least one of said dies. and means for electing the dried and finished article from the chine.

it. A. fibrous pulp molding machine comprising an intermittently revolving shaft, a forming die and a drying die mounted in angularly spaced 7 relationship on said shaft, means for heating said drying die, means for revolving said shaft step by step, a pulp tank carrying an aqueous fibrous pulp mixture in which the forming die is immersed during apart of its cycle for the suction formation or an article thereon, means for periodically lowering the pulp tank to'permit the revoluble drying die to revolve through its orbit without immersion in the pulp mixture, means for removing the wet formed article from the formin: die. and means for drying the removed wet -article under heat and mechanical pressure on forming die, a reciprocating drying die mounted outside the orbit of said revolving dies and complementai in shape to and adapted for timed coaction with said revolving dies, means timed to the intermittent rotation of said shaft for meeting said reciprocating drying die first with said iorming die to remove therefrom a wet article and thereafter with said revoluble drying die to drying die, means tor depositing wet pulp layers on said iorming dies, a. reciprocating drying die mounted outside the orbit at said revolv dies and complemental in shape to and adapted ifor till timed reaction with said revolving dies, means tor rotating said shalt step by step to bring the dies thereon into eoaetive alinement with said reciprocating die, means operative when said chart is paused in its rotation to enact said reciprotating die first with the forming dies to successively remove the wet articles therefrom and thereafter with a revoluble drying die to dry and finish the composite article between said reciprocating die and said last-named revoluble drying die under mechanical pressure and heat applied by at least one or said dies, and means for ejecting the finished article from the machine.

18. A fibrous pulp molding machine, comprisan intermittently revolving shaft, an articleiorming mechanism and an article-drying and finishing mechanism associated therewith, said article forming mechanism comprising a loraminous forming die mounted on said shaft to revolve therewith and means for depositing a wet pulp article on said formingdie, and said articledrying and finishing mechanism comprising a drying die mounted on said shaft to revolve therewith and a reciprocating drying die mounted outside the orbit of the revolving dies and complemental in shape thereto and adapted for timed coaction therewith, means for revolving said shaft step by step, means operative when said shaft is paused in its rotationfor first coacting said reciprocating die with the forming die to remove'the wet pulp layer therefrom and for thereafter coactlng said reciprocating die with 

